(1) Field of the Invention
The present invention relates to a thermal head for use in heat sensitive recording. More particularly, the present invention relates to a serial type thermal head in which printing of high quality can be performed without forming a blank space between printing dots while eliminating mutual thermal influences in heat-generating elements.
(2) Description of the Prior Art
In a conventional serial type thermal head, as shown in FIG. 6 of the accompanying drawings, a plurality of heat-generating resistor elements 12, which are selectively actuated, are arranged on a substrate 1 in a longitudinal line, and in order to avoid formation of a blank space in an area to be printed, the respective heat-generating resistor elements 12 are inclined at a predetermined angle with respect to the scanning direction (indicated by an arrow in FIG. 6) so that the lower edge portion 12a of each heat-generating resistor element 12 and the upper edge portion 12b of the adjacent heat-generating resistor element 12 overlap each other with respect to the scanning direction (see Japanese patent application Laid-Open Specification No. 141640/78).
However, this conventional thermal head involves the following problem. More specifically, since a plurality of heat-generating resistor elements 12 are arranged in a longitudinal line, the distance l between every two adjacent heat-generating resistor elements is very narrow and hence, mutual thermal influences in the adjacent heat-generating resistor elements 12 cannot be avoided. Accordingly, when printing is performed by selectively actuating one heat-generating resistor element 12 to generate Joule heat, the printing density greatly differs according to whether or not heat is generated in the adjacent heat-generating resistor element.